“I don’t think that in the last six months I have visited a country anywhere in the world where I have not been asked ‘what will be the economic consequences of Brexit?” she said.

‘Heck no!’

Asked if the Treasury had had any input into the IMF’s conclusions, Ms Lagarde responded: “Heck no! If you are suggesting that, you don’t know the IMF.”

In its report, the IMF said that a Brexit vote would result in a “protracted period of heightened uncertainty” and could result in a sharp rise in interest rates.

That would cause volatility on financial markets and economic output to decline and could also erode London’s status as a global financial centre, it added.

Priti Patel MP, who is backing the leave campaign, said the IMF was “wrong then and they are wrong now. It appears the Chancellor is cashing in favours to Ms Lagarde in order to encourage the IMF to bully the British people.”

Former chancellor, Lord Lamont, added: ‘This daily avalanche of institutional propaganda is becoming ludicrous and pitiful. Important institutions are being politicised and used to make blood-curdling forecasts.

“There are plenty of respected individual economists, plenty of respected professional investors, and plenty of entrepreneurs who take a very different view from Christine Lagarde and who have probably been better at foreseeing the future than the IMF.”

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Image caption
Priti Patel MP accused the IMF of ‘bullying’ UK voters

The Fund said it expected growth to fall below 2% for the full year in 2016 before returning to an average of 2.25% over the medium term.

However, the IMF said that this “broadly positive” forecast was subject to notable risks, the biggest of which was the EU referendum, but also the low level of household savings, high levels of household debt, a wide current account deficit and concerns that productivity growth will not rise significantly.

Concerns about a possible Brexit may have affected UK markets in recent months, according to the IMF.

It pointed to a 40% decline in the number of commercial real estate transactions in the first three months of the year.

Deciding whether to remain in the EU was a choice for voters to make, the IMF said, adding that “their decisions will reflect both economic and non-economic factors”.